The general operation process is as follows: first, lay a layer of fine quicklime on the bottom of a large empty cylinder (or iron drum), then lay a layer of clean wheat straw on the lime, and then put fresh duck eggs on the wheat straw layer by layer. When it is 90% full, cover it with bamboo sticks and press it with wooden sticks (to prevent duck eggs from floating out of the liquid surface when adding liquid). After the eggs are taken out of the pot, the mixed feed liquid of soda ash, salt, tea, plumbum preparatium powder, pine and cypress branches and clear water which is heated and boiled in the pot in advance is stirred to make its concentration uniform, and then it is slowly poured into the pot from the side of the pot until all fresh duck eggs are submerged by the feed liquid. After all this is done, technical management is needed.
The main technical management work is to observe and check frequently, especially when the temperature changes greatly, so as to find problems and deal with them in time. Fresh eggs are poured into the tank for about 30 days. If the feed liquid is normal, it can be discharged. After the eggs are taken out of the tank, 30% to 40% yellow mud is usually added to the waste liquid soaked in the eggs for more than three times to make a slurry with a certain viscosity, and the eggs are wrapped in the slurry one by one. In order to prevent muddy eggs from sticking to each other, eggs should be placed on the chaff and rolled back and forth immediately after being covered with mud, so that the chaff can stick to the mud evenly. In this way, the delicious preserved eggs are ready.
In the production, there are some operations worthy of attention. For example, the dosage of quicklime and soda ash should be flexibly controlled, and duck eggs should be used less when the quality is good, and more when the quality is poor; Yellow lead powder must be ground and sieved, the finer the better; Don't pour liquid violently, so as not to break fresh eggs and waste liquid; The feed liquid temperature should change with the seasons, which is about 65438 05℃ in the first quarter, 20℃ ~ 30℃ in summer and higher than 26℃ in winter. Fresh eggs should be inspected every 5-6 days at 25℃ ~ 30℃ and every 7-65,438+05℃ ~ 25℃. If these operations are wrong, it will be difficult to make preserved eggs with good flavor and aesthetic feeling.
The preserved egg made by this method is crystal clear in protein, and the yolk is clearly visible. It tastes delicious and has an endless aftertaste. Perhaps because of this, it is one of the special foods in China.
Advocate green food and introduce several lead-free processing methods;
1, making lead-free preserved eggs
Materials: 40 duck eggs, 360kg of quicklime, baking soda140g, salt160g, black tea powder 20g and ferrous chloride10g.
Boiling with 0.5 kg of water and 20 g of black tea powder, filtering, and putting the filtrate into a container; Add quicklime, soda ash, salt, ferrous chloride and 1.9 kg of water into the filtrate, stir properly, filter after it is completely acted, and take the filtrate for later use; Soak qualified fresh duck eggs in the filtrate gently, cover them with egg noodles or press them with heavy objects to prevent them from falling off the liquid surface, take them out after about two weeks of pickling, air-dry them and store them at room temperature for two weeks, and then they can mature into preserved eggs with good flavor.
Step 2 make preserved eggs
Materials: 5 kg of eggs, edible alkali150g, 200g of quicklime, 500g of plant ash, 300g of coarse salt, 500g of loess, 0/50g of red tea1200g of water.
Boil tea leaves into tea, pour them into a basin filled with quicklime, alkali and salt under heating, and when the temperature drops below 30℃, add loess and stir evenly, and finally put them into plant ash to make slurry with appropriate consistency for use; Put the qualified fresh eggs into the mud, turn them with a silk spoon to make the eggs stick to the mud with a thickness of about 3 mm, roll on the rice bran or sawdust, stick a layer of bran, and put them into the cylinder one by one to seal; At about 25℃,/kloc-0 ripens in 5 ~ 20 days. It is best to check 2 ~ 4 days in advance before opening the cylinder. If it is ripe, take it out to dry and save it.
3. Making preserved eggs without mud
Add 2kg of clean water to the pot, add10g of fennel, 20g of pepper and100g of black tea, boil for 5min, take out, add 300g of edible soda ash, and after it is completely dissolved, add a little pine or cypress leaves to make a soaking solution.
Put 50 washed duck eggs or eggs into a ceramic container, and pour the cooled soaking solution into the egg container to ensure that the eggs are completely submerged. If the liquid is not enough, add some cold boiled water. Then seal the container 10 ~ 14 days. Take it out and air it for 4 ~ 5 days. It was made into a preserved egg without mud.
4. Pickling of salted eggs
Salt mud coating method: for every 100 egg, use 0.75kg salt, 1 0g pepper and a little black tea, add10.5kg water, boil and cool, take1kg loess, make it into thick paste, if there is little water, add water, and then use the prepared yellow mud.
Question 2: How to process preserved eggs with eggs? Preparation method of preserved egg powder
1, raw material selection. Only three raw materials are needed to make preserved egg powder, which can be obtained everywhere. ① Lime. It is best to choose a large, light, impurity-free lump ash that produces strong bubbles when adding water and quickly turns to ash; ② Lithium base. You can directly buy caustic soda with few pores, dense texture and compact structure in the market, or you can make it yourself. 3 salt. Ordinary edible salt.
2. Production method. According to the production scale, lime, caustic soda and salt are respectively weighed according to the ratio of 3:3: 1, fully mixed, packed into 1 pouch every 250g, and sealed with a heat sealing machine to obtain the finished product (when there is no heat sealing machine, the tooth surface of a small hacksaw can also be sealed with candles). Each small bag can be processed into 50 preserved eggs.
Second, the preserved egg soaking processing method
After consumers buy back preserved egg powder, they add water to each bag (60 grams for each egg), and then slowly pour it into containers such as jars with fresh eggs to drown all the eggs. There is no need to move and turn the eggs halfway. Generally, it will mature only after soaking for 7- 10. It is very convenient to take them out one by one, wipe the immersion liquid and store them in plastic bags or cans. In the season when the price of eggs is high and the price is low, you can also build several small clay pots at home (soaking the size of each pot at a time).
Bubble processing 1000-2000 preserved eggs), self-made preserved egg powder to process preserved eggs in batches, and the benefits are good.
Question 3: Why can't preserved eggs be made of eggs? Most preserved eggs produced by traditional methods are duck eggs, but compared with duck eggs, the eggshell of eggs is thinner, the thickness is uneven and the thickness of capillary holes is different, so the quality of preserved eggs made from eggs is quite different and the stability is not enough. Because raw materials such as lime and soda ash are used to process preserved eggs, the pH value range of egg white solidification is too narrow, and protein will hydrate if it is not careful, so the technical requirements are high.
Therefore, to make preserved eggs with eggs as raw materials, we should first choose intact eggs with appropriate size without cracks, then check the size of air holes with light, and then control the pH value of the finished products from the aspects of soaking time, ambient temperature, humidity and packaging.
Eggshells made of preserved eggs can be completely peeled off, unlike duck eggs, which are easily broken. Protein is as crystal clear as amber, and its taste is smooth, not as soft as duck eggs.
Question 4: How are preserved eggs made? How is the original preserved egg made? According to legend, during the Taichang period of the Ming Dynasty, the owner of a small teahouse in Wujiang County, Jiangsu Province was very good at doing business, so his business was booming. Due to the shortage of manpower, the shopkeeper poured the brewed tea into the ashes when entertaining guests. Coincidentally, the shopkeeper also keeps several ducks and likes to lay eggs in the ashes. When the host picks up the eggs, it is inevitable that there are omissions. Once, the shopkeeper found many duck eggs while cleaning up the tea residue in the furnace ash. He thought they were inedible. Who knows, when you peel it off, it's dark and bright with white patterns on it. When you smell it, a special smell comes to your nose. Taste it, it's fresh and smooth. This is the earliest preserved egg. Later, after continuous exploration and improvement, the production technology of preserved eggs was improved day by day. On the other hand, preserved eggs originated in Tianjin. Word of mouth: About 200 years ago, the son of a wealthy family in a village in Tianjin made a coffin for his mother and put it in an empty house for later use. After a long time, his mother was still alive, so he ordered his family to sprinkle lime and plant ash on the coffin to prevent moisture, and left a big gap on the lid of the coffin for ventilation. Forget it when it's over. The following year, her mother died. She moved the coffin to the grave and found more than 100 eggs in plant ash. The dutiful son was angry and took it out and threw it away. The shell broke and the inside became a dark brown transparent crystal, which was very confusing. Some good people dare to taste it. It's delicious. The onlookers also felt strange, so they hurried to taste it, and the result was like this. Those who have insight will follow suit afterwards, putting fresh eggs in lime and plant ash, and so on. As a result, neighbors followed suit and called it "color-changing egg". For a long time, this original technology has been circulated in Jiangsu and Zhejiang provinces, and it has been improved repeatedly and improved day by day. As a brand-new food, color-changing eggs have been pushed to the market by Jiangsu and Zhejiang people who are good at business. Therefore, today's "preserved eggs" began in Tianjin and became in Jiangsu and Zhejiang.
Question 5: Can eggs be preserved eggs? Yes, you can.
Ingredients: eggs, water, boiled water, salt, plant ash or sawdust. Accessories: lime powder
1. Wash and dry the eggs.
2. Mix salt and plant ash with cold boiled water and add more salt. You can mix only a little at a time in proportion, and then mix after use.
3. Stir the eggs in the mixed mud until the eggs are completely wrapped and covered with a thin layer of mud.
4. Put the wrapped eggs in a container and put them in a cool place.
Note: adding lime powder to the mud can shorten the time, but it tastes almost lime.
Question 6: What are preserved eggs made of? Preserved egg is a unique processed egg in China, which is an alkaline food. Salt, tea and alkaline substances (such as quicklime, plant ash, sodium carbonate, sodium hydroxide, etc. ) are all materials needed for preserved eggs. Preserved eggs have a special flavor because the original thioamino acids are decomposed to produce hydrogen sulfide and ammonia under the action of strong alkali, which, together with the smell of raw materials in the soaking solution, produces a unique flavor. The color of preserved eggs is due to the fact that under the action of strong alkali, the protein part of protein will be reddish brown or dark brown, and the yolk will be dark green or orange red. How did the pine flowers on the preserved eggs come from? It is actually produced by a chemical reaction: the main chemical component of protein is a kind of protein. When eggs are kept for a long time, some protein in protein will break down into amino acids. Its chemical structure has a basic amino group -NH2 and an acidic carboxyl group -COOH, so it can interact with acidic and alkaline substances. Therefore, people are making preserved egg patterns and deliberately adding some alkaline substances to the mud. Such as lime, potassium carbonate, sodium carbonate, etc. They will combine with amino acids through the small holes in the eggshell to form amino acid salts. These amino acid salts are insoluble in protein, so they crystallize in a certain geometric shape to form beautiful pine flowers. Why is the yolk of preserved eggs blue and black? In fact, it is also caused by a chemical reaction: the main chemical component of preserved eggs is another kind of protein, which contains sulfur. After a long time, egg yolk will also be decomposed into amino acids, and what we usually call rotten egg-flavored gas-hydrogen sulfide will be released. Egg yolk itself contains many minerals, such as iron, copper, zinc and manganese. Hydrogen sulfide can react with these minerals to form sulfide. Therefore, the blue-black yolk is the source of these sulfides. Most of these sulfides are extremely insoluble in water, so they will not be absorbed by the human body. In addition, because a large amount of protein in preserved egg yolk is decomposed into amino acids, the taste of preserved egg yolk is much fresher than that of ordinary eggs. Preserved eggs are nutritious and delicious, but they are too alkaline to eat. Suggestion: add some old vinegar when eating preserved eggs. Old vinegar can sterilize and neutralize some alkalinity of preserved eggs, and it tastes more delicious.
Question 7: How to turn an egg into a preserved egg? Is there a simple, fast and high-quality indigenous method? Lime residue and bran can be mixed evenly to wrap the whole egg.
Question 8: How are preserved eggs made? The process of processing fresh eggs into preserved eggs is essentially a complex chemical reaction process. Although there are many formulas and techniques for processing preserved eggs, the main raw materials generally include: calcium oxide (CaO), soda ash (Na2CO3), plant ash (mainly K2CO3), salt, tea and so on. According to the actual situation of students, this paper takes two preserved eggs as examples to explain how to process preserved eggs in the laboratory and its chemical principle:
Length grey matter formula
The preserved eggs on the dining table are delicious, but they are covered with an ugly coat. Don't underestimate it, it is the key to making preserved eggs, and this is ash. The formula of the ash material is: 50g of quicklime, 3g of soda ash, 2g of plant ash 1 g, 2g of salt, 20g of water and trace of tea.
2. Grey material modulation
According to the requirements of ash formula, put the required ash into a container (only a large beaker is needed) and mix it with water. Quicklime first reacts with water to produce hydrated lime, and then the hydrated lime reacts with potassium carbonate, the main component of soda ash and peat, to produce sodium hydroxide and potassium hydroxide respectively. The chemical equation of this reaction is expressed as follows:
Calcium oxide +H2O = calcium hydroxide
Calcium hydroxide+sodium carbonate = calcium carbonate ↓+sodium hydroxide
Calcium hydroxide+potassium carbonate = calcium carbonate ↓+potassium hydroxide
In order to make the substances in the hair fully react, it can only be used after 24 hours of preparation.
3. Preserved egg processing
Roll fresh eggs in the prepared ash several times, so that the surface of the eggshell is evenly coated with a layer of ash powder, and then roll them into rice chaff or sawdust several times after taking them out, so that a layer of rice chaff or sawdust sticks to the ash. Squeeze it gently by hand to make it tight, and put it in a container prepared in advance. The second fresh egg is also treated in this way. Seal the container and place it in an environment with an ambient temperature of 65438 08 ~ 24℃. /kloc-can be eaten after 0/0 days.
In this 10 day, the inside of the egg is not as calm as a deep pool. The strong alkali (NaOH, KOH) in the ash material penetrates into the egg white and egg yolk through the eggshell, and reacts with protein in the egg white and egg yolk, so that protein decomposes, solidifies and releases a small amount of hydrogen sulfide (H2S) gas. At the same time, the infiltrated alkali will further neutralize the amino acids decomposed by protein, and the crystals of the generated salt will be deposited in the preserved egg protein of the gel peptide, resulting in a white "pine flower" (which is also the reason for the name of preserved egg). However, hydrogen sulfide gas reacts with minerals in egg white and egg yolk to produce various sulfides, so the colors of egg white and egg yolk have changed, with egg white showing a special dark brown color and egg yolk showing a dark green color. Salt can shrink preserved eggs from eggshells and increase their taste. Tannin and aromatic oil in tea can color the solidified protein and increase the flavor of preserved eggs.
And why can't preserved eggs go bad for half a month or even months? First, because there is salt in it, salt has antiseptic effect; First, alkaline substances kill bacteria in fresh eggs that may lead to protein's spoilage.
10 days later. When you sit at the table and taste this delicious preserved egg, your heart will be filled with joy, and you will think about when to cook more. But next time you prepare for mass production, don't forget to change the formula of ash in proportion.
Question 9: Are preserved eggs made of eggs or duck eggs? Preserved egg is a unique processed egg in China, and it is also an alkaline food. Salt, tea and alkaline substances (such as quicklime, plant ash, sodium carbonate, sodium hydroxide, etc. ) are all materials needed for preserved eggs. Preserved eggs have a special flavor because the original thioamino acids are decomposed to produce hydrogen sulfide and ammonia under the action of strong alkali, which, together with the smell of raw materials in the soaking solution, produces a unique flavor. The color of preserved eggs is due to the fact that under the action of strong alkali, the protein part of protein will be reddish brown or dark brown, and the yolk will be dark green or orange red. Sometimes the yolk is yellow, which means that this preserved egg may not be very fresh, so it's best not to eat it!
Nutritional value of preserved eggs
The nutritional components of preserved eggs are quite similar to those of ordinary eggs, and the curing process has experienced the action of strong alkali, so protein and lipids are decomposed, which is easier to digest and absorb, and cholesterol is also reduced. Pickled with iron agent, so the iron content is also high. However, vitamin B and essential amino acids were destroyed.
In the traditional preserved egg processing, heavy metals such as lead or copper are usually added to the dipping solution to solidify protein. According to the regulations of Taiwan Province Provincial Health Department, the lead content of preserved eggs should not exceed 2ppm, and the copper content should not exceed 8ppm. Moreover, agricultural administrative units also help manufacturers to produce high-quality preserved eggs, so that the lead content does not exceed 0.3ppm and the copper content does not exceed 5ppm. Therefore, most of the soaking solutions of qualified manufacturers do not add heavy metals or have little content.
The preserved egg of Songhua is characterized by white needle-like crystals in protein. Some people think that this kind of protein is especially nutritious. This is because iron phosphate is added in the processing. Therefore, compared with ordinary preserved eggs, only iron content is higher, and other nutritional components are no different.
At present, preserved eggs on the market include duck eggs or preserved eggs, which can be selected according to personal preferences. When buying preserved eggs, you can pay attention to whether there is a quality certification mark. In addition, preserved eggs with high lead and copper content will have more spots on the eggshell surface, and protein can be seen to be dark green or occasionally black spots after shelling, which is not suitable for purchase. Some preserved eggs made by traditional methods will be covered with red soil and straw, which is unsanitary and inconvenient to judge the lead content by appearance, so it is not suitable for purchase. It is recommended to buy products with complete packaging and clear labels. Pay attention to the date of production when buying, and pay attention to the way and period of preservation when going home to save.
1. Extreme neurotoxicity: Lead can damage the brain and nerves, making people mentally retarded, unresponsive, hyperactive, inattentive, hearing impaired, learning difficulties and dyskinesia.
2, cause anemia
3. Suppress immunity
4. Loss of appetite, unexplained abdominal pain, vomiting, diarrhea or defecation.
5, affect the absorption and utilization of minerals and vitamins. Lead to calcium deficiency, zinc deficiency and iron deficiency.
Could you please introduce it in more detail?